CSNY 1974, a box set of the band's 1974 tour, is out today, 40 years after it was recorded and four years after Graham Nash started work on it.

Nash says, "It was a very interesting technological project. The idea was to put you in a hall and make sure that you understood that it was one show that you were seeing, even though we did multi-track nine shows." Looking back on that tour, Nash adds, "It was incredible. Immense crowds. We were incredibly popular. The Beatles had done Shea Stadium [in New York] and The Rolling Stones had done some incredibly large gigs at Hyde Park in London, but this was the first tour of 31 shows of those kinds of places [arenas and stadiums]."

CSNY 1974 contains 40 songs and is available in multiple formats. The multi-disc sets contain a bonus DVD of eight songs captured at the Capital Center in Landover, Maryland and Wembley Stadium in London, along with a 188-page book. CSN, minus Neil Young, will celebrate today's release with the first of three shows this week at the Beacon Theatre in New York.

And...a bonus. From The Tonight Show with Jimmy Fallon, "Neil Young" sings Fancy with Crosby, Stills & Nash.